1. Field of the Invention
The present invention relates to a treatment cup cleaning method, a substrate treatment method and a substrate treatment apparatus. Exemplary substrates to be treated by the substrate treatment method and the substrate treatment apparatus include semiconductor wafers, substrates for liquid crystal display devices, substrates for plasma display devices, substrates for FED (Field Emission Display) devices, substrates for optical disks, substrates for magnetic disks, substrates for magneto-optical disks, substrates for photo masks, ceramic substrates and substrates for solar cells.
2. Description of Related Art
In production processes for semiconductor devices, liquid crystal display devices and the like, substrates such as semiconductor wafers and substrates for the liquid crystal display devices are treated with a treatment liquid. A substrate treatment apparatus of a single substrate treatment type adapted to treat a single substrate at a time, for example, includes a spin chuck which horizontally holds and rotates the substrate, a nozzle which supplies the treatment liquid to a front surface of the substrate held by the spin chuck, and a bottomed treatment cup which accommodates the spin chuck.
The treatment cup includes a guard having an inner wall which receives treatment liquid scattering around the substrate, and a cup which receives treatment liquid moving down on the inner wall of the guard. The treatment liquid moving on the guard is collected in the cup on a lower edge of the guard.
Where a chemical liquid is used as the treatment liquid, the chemical liquid is liable to be dried to be crystallized on the inner wall of the guard. Problematically, this may result in particles to contaminate the substrate. Therefore, it is desirable to clean the inner wall of the guard with a cleaning liquid to remove substances deposited on the inner wall.
US Patent Application No. 2012/0273011 A1 states that a rotary base of the spin chuck is rotated at a predetermined rotation speed and, in this state, the cleaning liquid is supplied to an upper surface of the rotary base, whereby the inner wall of the treatment guard is cleaned with cleaning liquid scattering from the upper surface of the rotary base. The guard includes a hollow cylindrical portion and an inclination portion provided integrally with the cylindrical portion as extending from an upper edge of the cylindrical portion obliquely upward toward a center axis of the cylindrical portion.